The Problem
After installing Microsoft Core fonts on ubuntu, firefox crashed when loading pages. When trying to load firefox from the shell, the following message is received


(gecko:6422): Pango-WARNING **: failed to create cairo scaled font, expect ugly output. the offending font is ‘Arial 12′
Segmentation fault (core dumped)


Solution:
This problem is caused by permissions of the newly installed fonts, so just resetting permissions using the following command:


sudo chmod -Rv 775 /usr/share/fonts/


[Solution]
sudo apt-get install gnome-vfs-obexftp